Frictionless cam operated apparatus

ABSTRACT

A cam-operated mechanism wherein fritionless roller bearing means are provided between an eccentric cam member and a reciprocating member driven thereby. The cam and reciprocating member are described in particular application to an embossing press or the like, wherein an eccentrically mounted roller is maintained in contact with a vertically movable stamping plate. Roller bearing means are provided surrounding the eccentric roller and interposed between the roller and the stamping plate, whereby the eccentric roller is free to rotate within the roller bearing means, which bearing means are given a substantially frictionless rocking or rolling motion upon the vertically movable stamping plate.

United States Patent 1 Lewis et al.

FRICTIONLESS CAM-OPERATED APPARATUS [451 July 17,1973

2,047,373 7/1936 Kingsley 101/9 Primary Examiner-Charles J. MyhreAssistant Examiner-Wesley S. Ratliff, J r. Attorney-Morris SpectorABSTRACT A cam-operated mechanism wherein fritionless roller bearingmeans are provided between an eccentric cam member and a reciprocatingmember driven thereby. The cam and reciprocating member are described inparticular application to an embossing press or the like, wherein aneccentrically mounted roller is maintained in contact with a verticallymovable stamping plate. Roller bearing means are provided surroundingthe eccentric roller and interposed between the roller and the stampingplate, whereby the eccentric roller is free to rotate within the rollerbearing means, which bearing means are given a substantiallyfrictionless rocking or rolling motion upon the vertically movablestamping plate.

11 Claims, 4 Drawing Figures PAIENIEU JUL 1 7 I913 F I G 4 ALVIN LEWISANTHONY J. DESTITOI s FIG.2

1 FRICTIONLESS CAM-OPERATED APPARATUS BACKGROUND OF THE INVENTION Thisinvention relates generally to cam movements, and particularly to amechanism in which an eccentric cam member actuates a reciprocatingmember in periodic fashion.

In known cam-operated mechanisms of the general character described, aneccentric rotatable cam member generally bears directly upon areciprocatable follower member, which follower member is normally biasedto provide continuous contact with the cam member. Due to the sliding orrubbing contact between the cam and the follower, a considerable amountof work is required merely to overcome the frictional forces therebetween, and additionally, a considerable wear of the moving parts isexperienced.

A typical application of such cam mechanisms resides, for example, inembossing presses and similar devices. Such embossing presses are wellknown in the art, and may, for example, be used for pressing anembossable material into an embossing die. In a typical knownconstruction of such embossing presses, an eccentric roller defining acam means, which is rotatable by means of a manual handle or otheroperating means secured thereto, bears against a stamping plate which isvertically movable and which is biased upwardly by springs or otherbiasing means to press at all times against the eccentric roller,whereby when the roller is rotated, the eccentric portion thereof willmove the stamping plate downwardly to engage and emboss the material.

A major drawback of such known embossing presses is that, since theeccentric roller contacts in sliding manner the upper surface of thestamping plate, there is considerable friction between the eccentricroller and the stamping plate, and hence a considerable amount of torquemust be applied to the roller to overcome this friction force. Thus, forexample, such embossing machines of known construction generally arerequired to have extremely long operating handles or levers in order toprovide such torque. In addition, this high friction between theeccentric roller and the stamping plate results in extremely rapid wearof the contacting parts, necessitating frequent repairs and/orreplacement of the worn parts.

SUMMARY OF THE INVENTION With the above background in mind, it istherefore an object of the present invention to provide an improvedcam-operated mechanism.

Specifically, it is a primary object of this invention to provide such acam-operated mechanism which substantially eliminates sliding frictionbetween the eccentric cam roller and the reciprocating plate or followermember.

It is a further object of this invention to provide such a mechanismwhich may be hand-operated and which requires considerably less force tooperate as compared with prior known devices.

It is yet a further object of the present invention to provide such amechanism in which wear of the moving parts is markedly reduced incomparison to known devices.

Still a further object of the present invention is to provide anembossing press or similar device incorporating the novel cam-actuatedmechanism.

These, as well as other objects which will become apparent as thedescription proceeds, are implemented by the inventive devicecharacterized by an eccentric roller which in a preferred embodiment isadapted to be rotated by means of a hand-operated lever. A verticallymovable plate is maintained in constant contact with the eccentricroller by means of biasing springs or other biasing means, and rollerbearing means are provided surrounding the eccentric roller andinterposed between the plate and the eccentric roller for providingrocking movement of the roller bearing means relative to the plate andsubstantially eliminating sliding friction therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS The invention itself will be betterunderstood, and additional objects, advantages and features thereof willbecome apparent, from the following detailed description of a preferredembodiment of the invention, taken in conjunction with the accompanyingdrawing, in which: 7

FIG. 1 is a perspective view of a hand-operated embossing deviceutilizing the cam mechanism of the present invention;

FIG. 2 is an end vertical sectional view through the device of FIG. 1,taken along lines 2-2 of FIG. 3;

FIG. 3 is a front elevational view, partially in section, looking alonglines 3--3 of FIG. 2; and

FIG. 4 is an enlarged fragmental view showing the manner in which theoperating handle is secured to the eccentric roller.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings,there is shown in FIG. 1 a preferred embodiment of a hand-operatedembossing device incorporating the novel cam mechanism of thisinvention, comprising a pair of end upright support members 10 and 12,respectively, and a die support member 14 secured therebetween adjacentthe bottom thereof by means of set screws or the like 16. The endsupport members 10 and I2 and the die support member 14 may be formed byany suitable method, such as by casting and/or machining.

A vertically movable stamping plate member 18 extends u'ansverselybetween the upright supprot-membars 10 and 12 and is guided for limitedvertical movement therebetween by means of a pair of guide flanges 20which travel within and are guided by a pair of vertical guide slots orrecesses 22 in the interior surfaces of the respective end supportmembers 10 and 12. The stamping plate member 18 is biased upwardly bymeans of biasing means such as coil springs 24 at the opposite endsthereof, so that the stamping plate member is maintained in continuouscontact with the lower surface of an eccentric operating cam rollermeans, which roller means will be described in greater detail hereunder.The lower ends of the springs 24 abut against stationary stops which maybe formed by the upper surfaces of respective stub screws 26 withinvertical bores 28. The vertical bores 28 may, for example, form downwardextensions of the guide slots 22.

Eccentric rotatable cam roller means, generally designated by referencenumeral 30, are provided for effecting intermittent downward movement ofthe stamping plate member 18 upon rotation of such roller means and thusemboss the embossable material between such stamping plate member and asutiable die supported by the guide support surface 14. As best seen inFIGS. 2 and 3, the cam roller means 30 include a pair of axially spaced,reduced diameter end bearing portions 32 rotatably journalled by anysuitable means, such as by roller bearing means 34, within therespective upright support members and 12 and extending therebetween,adjacent the upper ends thereof. An elongated central eccentric shaftportion, of enlarged diameter with respect to these end bearing portions32, extends axially between and is rigidly secured to the end bearingportions, and is radially off-set with respect thereto, as is best seenin FIG. 2.

Such central eccentric shaft portion, designated by reference numeral36, customarily in conventional embossing presses of this general naturecontacts the upper surface of the stamping plate member 18, wherebyrotation of the cam roller means 30, due to the eccentricity of thecentral radially off-set portion 36, will move the stamping plate member18 downwardly to thus emboss the embossable material. In suchconventional constructions, it is clear that considerable rubbing orsliding friction will be encountered between the rotating eccentricportion of the cam roller means and the upper surface of the stampingplate, particularly since the upward biasing means such as the springs24 generally press the stamping plate against the roller means withconsiderable force. Accordingly, in this invention, novel substantiallyfrictionless means are provided for substantially reducing slidingcontact between the eccentric portion 36 of the roller means and theupper surface of the stamping plate means 18. As shown in FIGS. 2 and 3,such means comprise outer rotatable sleeve means 38 surrounding theeccentric shaft portion 36 in concentric relation thereto, the sleevemeans 38 being rotatable with respect to such eccentric shaft portion.Additionally, to further reduce the operating friction of the inventivepress, frictionless bearing means are provided between the eccentricshaft portion 36 and the outer rotatable sleeve means 38 to providesubstantially frictionless rolling contact therebetween; as shown, suchbearing means may preferably comprise roller bearing means 40 about theperiphery of the eccentric shaft portion 30 and utilizing such eccentricshaft portion as an inner race and the concentric sleeve 38 as an outerrace therefor.

The outer concentric rotatable sleeve 38 may be formed as a singlesleeve extending the full axial length of the eccentric shaft portion36; however, preferably and as shown, the sleeve means comprise aplurality of axially aligned sleeve sections which are individuallyrotatable with respect to one another, to compensate for minor play ornon-linearity between the lower surface of the sleeve and the uppersurface of the stamping plate means 18. If a plurality of such sleevesegments are provided, then the roller bearing means 40 may likewisecomprise a plurality of individual roller bearing segments correspondingto each of the individual rotatable sleeve segments.

Suitable means may be provided for rotating the eccentric roller meanscomprising the end bearing portions 32 and the central eccentric shaftportion 36, in order to effect downward embossing movment of thestamping plate member 18. In a preferred embodiment of the invention,such means may comprise a manually operated handle means 42non-rotatably secured to one of the end bearing portions 32, wherebyrotation of the handle will thus rotate the cam roller means therewith.As perhaps best seen in FIG. 4, the handle means 42 may, for example, bekeyed to the end bearing portion 32 by means of a non-circular slot 44in the handle means cooperating with a similar non-circular projection46 on the end bearing portion 32, and the handle may then be secured tosuch extension by means of suitable securing means such as a screw 48.Suitable stop means, such as an abutment member 50 secured to theappropriate upright support member 10, may be provided for limiting theamount of rotation of the handle 42 and hence the degree of upward anddownward travel of the stamping plate member 18.

While the operating means for the eccentric cam roller means has beenshown as comprising a manual handle, it should be understood that theinvention contemplates the use of any equivalent operating means,

as, for example, motor means driving the roller intermittently orcontinuously through a suitable gear train or through an oscillatingcrank drive.

It will be appreciated that, inasmuch as the sleeve member 38surrounding the eccentric shaft portion 36 is free to rotate relative tosuch eccentric shaft portion 36, the sleeve portion 38 will remain, froma rotational point of view, substantially motionless relative to thestamping plate member 18, while the eccentric shaft portion 36 rotatestherein. Thus, as opposed to the high degree of friction encountered inprevious known embossing presses of this character, where the eccentriccam roller directly contacted the stamping plate member, only a rockingtype of motion is encountered between the outer sleeve member 38 and theupper surface of the stamping plate member 18. Additionally, due to theprovision of the roller bearing means 40 between such outer sleeve 38and the eccentric shaft portion 36, as well as the roller bearing means34 between the end bearing portions 32 and the end support members l0and 12, substantially frictionless rotation is achieved between the camroller and the outer shaft member. Accordingly, it should be thereforeappreciated that a substantially frictionless operation of the device isachieved and accordingly, considerably less operating force is requiredto achieve a given downward force of the stamping plate member 18. Thus,for example, the length of a manual operating handle such as the handle42 shown, may be considerably shortened and less torque is required torotate the eccentric cam roller means. Further, due to such reducedfriction, it should also be appreciated that a considerably reduced wearof the realtively moving parts is achieved, resulting in a considerablyincreased life of the device and hence a reduction in the cost ofreplacement parts and repair.

While the invention has been described as particularly regarding anembossing press embodying the novel cam-operated means, it should beunderstood that such cam-operated means may find utility in anyapplication wherein it is desired to operate a reciprocating orotherwise periodically moving follower member by means of an eccentriccam means. Thus, for example, the cam-operated means of this inventionmay be utilized to operate tappet-valves in intemalcombustion engines,punch presses, cam-operated clamps and other holding devices, tablettingmachines and similar measuring machines, or any other suitableapplication.

Through the provision of an embossing device as described above, it isbelieved clear that all of the objects set forth at the outset to thespecification have been successfully fulfilled. ACCORDENGLY,

What is claimed is:

1. Apparatus comprising a pair of parallel spaced apart support members,a longitudinal plate member extending between the support members, meansforming cooperating surfaces on the plate member and on the supportmembers for guiding the plate member for reciprocating movement in astraight line substantially at right angles to the longitudinal axis ofthe plate member, eccentric cam means for effecting reciprocatingmovement of said plate member, said cam means including a cam roller,means journalling the cam roller at said support members for rotationabout an axis substantially parallel to the longitudinal axis of theplate member, said cam means extending from one'to the other of saidsupport members and bearing on said plate member at a number oflocations distributed along the length of the plate between the supportmembers, biasing means maintaining said plate member in continuouscontact with said cam means, and antifriction means disposed betweensaid cam means and said plate member for providing substantiallyfrictionless contact between the cam means and the plate member atspaced apart locations between the supporting members.

2. An apparatus as defined in claim 1, wherein said last-named meanscomprises a rotatable sleeve surrounding said eccentric cam roller meansand rotatable with respect thereto.

3. An apparatus as defined in claim 2, further comprising substantiallyfrictionless heating means dis posed between said rotatable sleeve andsaid eccentric cam roller means for providing substantially frictionlessrotation of said sleeve means relative to said eccentric cam rollermeans.

4. An apparatus as defined in claim 3, wherein said frictionless bearingmeans comprises roller bearing means.

5. An apparatus as defined in claim 2, further comprising means foreffecting rotation of said eccentric cam roller means to thereby effectreciprocating movemet of said plate member.

6. An apparatus as defined in claim 5, wherein said means for effectingrotation of said eccentric cam roller means comprises a handle meanssecured to said eccentric cam roller means to effect manual rotationthereof.

7. An apparatus as defined in claim 2, wherein the apparatus comprisesan embossing press or similar article, further comprising a die supportmember, said plate member comprising a stamping plate memberreciprocable with respect to said die support member to emboss anembossable material therebetween.

8. Apparatus as defined in claim 1 wherein said cam means includessleeve means surrounding the cam roller and the anti-friction means.

9. Apparatus as defined in claim 8 wherein the sleeve means comprisesaxially aligned sleeve sections which are individually movable withrespect to one another.

10. Apparatus as defined in claim 9 wherein the antifriction meanscomprises sets of roller bearing segments, the respective sets beingindividual to the respective sleeve segments.

11. Apparatus as defined in claim 1 wherein there is a guide supportbetween the support members and spaced from but substantiallycoextensive with the length of the plate member, said plate member beingmovable towards and from the guide support, said cam means distributing,along the length of the plate, the pressure exerted by the plate uponwork that may be upon the guide support.

1. Apparatus comprising a pair of parallel spaced apart support members,a longitudinal plate member extending between the support members, meansforming cooperating surfaces on the plate member and on the supportmembers for guiding the plate member for reciprocating movement in astraight line substantially at right angles to the longitudinal axis ofthe plate member, eccentric cam means for effecting reciprocatingmovement of said plate member, said cam means including a cam roller,means journalling the cam roller at said support members for rotationabout an axis substantially parallel to the longitudinal axis of theplate member, said cam means extending from one to the other of saidsupport members and bearing on said plate member at a number oflocations distributed along the length of the plate between the supportmembers, biasing means maintaining said plate member in continuouscontact with said cam means, and antifriction means disposed betweensaid cam means and said plate member for providing substantiallyfrictionless contact between the cam means and the plate member atspaced apart locations between the supporting members.
 2. An apparatusas defined in claim 1, wherein said last-named means comprises arotatable sleeve surroundiNg said eccentric cam roller means androtatable with respect thereto.
 3. An apparatus as defined in claim 2,further comprising substantially frictionless bearing means disposedbetween said rotatable sleeve and said eccentric cam roller means forproviding substantially frictionless rotation of said sleeve meansrelative to said eccentric cam roller means.
 4. An apparatus as definedin claim 3, wherein said frictionless bearing means comprises rollerbearing means.
 5. An apparatus as defined in claim 2, further comprisingmeans for effecting rotation of said eccentric cam roller means tothereby effect reciprocating movemet of said plate member.
 6. Anapparatus as defined in claim 5, wherein said means for effectingrotation of said eccentric cam roller means comprises a handle meanssecured to said eccentric cam roller means to effect manual rotationthereof.
 7. An apparatus as defined in claim 2, wherein the apparatuscomprises an embossing press or similar article, further comprising adie support member, said plate member comprising a stamping plate memberreciprocable with respect to said die support member to emboss anembossable material therebetween.
 8. Apparatus as defined in claim 1wherein said cam means includes sleeve means surrounding the cam rollerand the anti-friction means.
 9. Apparatus as defined in claim 8 whereinthe sleeve means comprises axially aligned sleeve sections which areindividually movable with respect to one another.
 10. Apparatus asdefined in claim 9 wherein the anti-friction means comprises sets ofroller bearing segments, the respective sets being individual to therespective sleeve segments.
 11. Apparatus as defined in claim 1 whereinthere is a guide support between the support members and spaced from butsubstantially coextensive with the length of the plate member, saidplate member being movable towards and from the guide support, said cammeans distributing, along the length of the plate, the pressure exertedby the plate upon work that may be upon the guide support.